Interesting, did you get any pictures?
I’m not sure if I’m understanding it right, like a rack and pinion. the pulley rides on the belt? If that is it, belt teeth up is bad because it traps dirt causing wear to the belt as the pulley grinds the debis into it, and tooth engagement. Using these small pulleys you need to wrap the belt around and engage as many teeth as possible or you you get the possibility of slipping.
I need to catch the next maker faire.